Visual Expetise

Question 1

FFA expertise

Answer 1

We see faces everyday, so we’re very good at recognizing them. The FFA is also active in people who are experts on other things, eg birds or cars.

It’s more of a visual expertise area than just a face area.

Question 2

Counter arguments for expertise

Answer 2

Prosopagnosic sheep farmer;
- Could still recognize individual sheep but not faces

‘Zooagnosic’ farmer:
Couldn’t recognise cows but could recognize faces of people

This would be impossible if the damaged areas were general visual expertise areas

Question 3

Capgras Delusion

Answer 3

Condition where after lesions, patients recognise others but believe they have been replaced by replicas/imposters

Ramachandran’s hypothesis was that the analysis of face recognition is done in FFA to identify, but at the amygdala to signal a certain feeling that goes along with that identity. In Capgras this would be disturbed

Question 4

Tests of remachandran’s hypothesis

Answer 4

Tested autonomic response (SCR) to familiar faces, found that Capgras patients don’t have increased automatic response.

In prosopagnisics, he tested this response in familiar people. They couldn’t name them, but the SCR response was above chance level (80%)

Question 5

Flashed face distortion effect (FFDE)

Answer 5

Test where two faces get mixed up after looking at them for a while

Works like this;
- Neurons encoding one face adapt, when seeing new face;’neurons encode the difference between the two.
- The difference between them is exaggerated, hence the distortions
- It’s not face specific, as inversion/manipulation of features has little effect.
- Size, duration and eccentricity matters a lot more (general peripheral adaptation effect, just more interesting with faces)